This invention is in the field of machines for moving soil and in particular such machines where the soil is scraped up by a scraping blade and spread with a rotating disc.
Machines for and moving soil are numerous and of many varieties. They are used in many varied situations where it is required to move soil for one reason or the other.
In some situations it is required to pick up soil at one location and transport it to another. In the case of road building for instance, the contour of the ground is changed to form a road by taking the soil from one location and placing it in another. Not only must the soil be removed from one location, it must also be placed in another specific location.
In many situations however, it is only desired to remove the soil from its current location, and the location it is moved to is not critical. Often it is desired to simply spread the removed soil so that it does not interfere with future operations on the land. An example is where ditches are made to drain standing water from ponds on agricultural lands.
Conventional soil moving machines include scrapers and loaders, where a generally horizontal blade is moved at a shallow depth along the ground, lifting soil and moving same into a bucket where it remains until dumped. Scrapers may incorporate a chain elevator to assist in moving the soil into the bucket. Trenchers or ditchers generally move the soil from the trench and pile it beside the trench, although ditchers are also known which spread the soil that is removed. Such soil-spreading ditchers are disclosed in U.S. Pat. Nos. 3,624,826 to Rogers, U.S. Pat. No.5,237,761 to Nadeau et al., U.S. Pat. No. 5,113,610 to Liebrecht et al., and U.S. Pat. No. 6,226,903B1 to Erickson.
The ditch cleaning apparatus of Rogers comprises a disc rotating in a substantially vertical plane. The apparatus rides on skids and is designed essentially to clean existing ditches. The ditcher of Nadeau et al. similarly comprises a disc rotating in a substantially vertical plane and having rippers ahead of the disc. The disc of Nadeau et al. disperses the soil loosened by the rippers. The apparatuses of Rogers and Nadeau et al. leave a ditch with a rounded bottom having a radius substantially equal to the radius of the disc.
The apparatus of Liebrecht et al. uses a spinning disc to both cut and spread the soil. The plane of the disc is oriented at a shallow angle of 15-30 degrees above horizontal, and a shallow angle to one side of 10-30 degrees.
The apparatus of Erickson uses a blade to scrape up soil and deposit it onto a spinning disc that has a plane oriented at less than 45 degrees above horizontal. The blade raises the soil onto a pan and then the soil passes over the pan and onto the disc which has an edge that is juxtaposed to a semi-circular cut-out in the pan. The disc rotates at a relatively shallow angle so that the soil is not raised very much before it is thrown off the disc. A beater may be provided above the pan to push the raised soil down onto the disc as it leaves the pan.
In the Erickson apparatus, because the disc edge is juxtaposed to the cut-out in the pan, the soil falls from the pan onto the very outside of the disc, placing maximum torque on the drive train. Dropping the soil onto a mid-point of the disc removed from the edge would reduce the power requirement of the apparatus. Then as the disc rotated and carried the soil to the discharge, centrifugal force would cause the soil to slide to the edge and off the disc and be spread over the adjacent ground. Dropping soil on an inner portion of the disc also would improve the spread. Soil dropped on the edge of the disc has only a small distance to travel before being thrown off the disc, so that the soil will be spread predominantly on one side. Soil that falls on an inner portion of the disc must first travel to the edge of the disc before being expelled at some point further along in the rotational direction.
The Erickson apparatus also does not allow soil to be thrown out of deeper ditches because the disc angle is shallow, less than 45 degrees above horizontal. A predominant object of the Erickson apparatus is to operate with a reduced power requirement. The shallow angle does reduce the power requirement since the soil is not lifted as high as would be the case with a steeper angle above 45 degrees. However by depositing the cut soil on a mid-point of the disc, sufficient power could be saved such that the angle could be increased, allowing the apparatus to work in a wider variety of ditch depths.
It is an object of the present invention to provide a scraper apparatus for removing a layer of soil and spreading the removed soil across the ground adjacent to the apparatus. It is a further object of the invention to provide such an apparatus with an improved spread pattern. It is a further object of the invention to provide such an apparatus that can spread soil out of deeper ditches than prior art machines.
It is a further object of the invention to provide such an apparatus where cut soil falls onto an inner portion of a disc and is thrown to the edge of the disc by centrifugal force, thereby improving the spread and reducing the power requirements of the disc and allowing the disc to be oriented at a higher angle to allow soil to be thrown out of deeper ditches.
The invention provides, in one aspect, an apparatus adapted for travel along the ground in an operating travel direction for cutting a layer of soil and spreading the cut soil over the ground adjacent to the apparatus. The apparatus comprises a disc rotatably mounted on the apparatus, the disc having a rotational plane sloping backward and upward from a lower portion of the apparatus at an angle between 45 and 75 degrees above a horizontal plane. The disc has a top surface that includes an annular outer portion adjacent to an outer edge of the disc, and an inner portion, and a plurality of spreading, members are oriented upright on the top surface of the disc. A blade is mounted on a lower front portion of the apparatus ahead of and below the outer edge of the disc and operative to cut a layer of soil. A pan extends from the blade rearward and over the outer portion of the top surface of the disc such that soil cut by the blade can flow over the pan and onto the inner portion of the top surface of the disc, but is substantially prevented from flowing onto the outer portion of the top surface of the disc. A kicker is rotatably mounted above the blade about a kicker axis transverse to the operating travel direction. The kicker is operative to propel soil cut by the blade in a direction rearward and toward a center of the apparatus and a drive is operative to rotate the disc and the kicker.
The invention provides, in a second aspect, an apparatus for cutting a layer of soil and spreading the cut soil over the ground adjacent to the apparatus. The apparatus comprises a frame adapted for travel along the ground in an operating travel direction and a blade mounted on a lower front portion of the frame and operative to cut a layer of soil. A disc is rotatably mounted on the frame behind the blade, the disc having a rotational plane sloping backward and upward from a lower portion of the frame at an angle between 45 and 75 degrees above a horizontal plane. A plurality of spreading members are oriented upright on a top surface of the disc. A pan is mounted on the frame and extends from the blade rearward to a location above the top surface of the disc removed from an outer edge of the disc such that soil cut by the blade can flow over the pan and onto the top surface of the disc, but is substantially prevented from falling onto an outer portion of the top surface of the disc that is in proximity to an outer edge of the disc. A kicker is rotatably mounted on the frame above the blade about a kicker axis transverse to the operating travel direction and the kicker is operative to propel soil cut by the blade in a direction rearward and toward a center of the apparatus. A drive is operative to rotate the disc and the kicker.
The apparatus uses a backward sloping disc to spread soil oriented at a higher angle than prior art machines, enabling it to throw soil out of deeper ditches while still cutting a essentially flat bottom ditch, rather than the arced bottom ditch of vertical disc machines. The plate and kicker are operative to direct more soil to inner portions of the disc than is possible with prior art machines. Directing soil to the inner disc portions reduces power requirements and improves spread, since soil nearer the center must move farther before reaching the edge and being expelled from the disc surface. This inner deposited soil thus exits the disc at a later point in the disc rotation than that nearer the edge.
The apparatus can also include a pendulum to indicate slope of the blade from side to side to an operator, and controls to adjust the slope of the blade.